Resonator for single-circuit magnetron



Nov. 28, 1 961 A. CHRISTEN ET AL RESONATOR FOR SINGLE-CIRCUIT MAGNETRON Filed. Nov. 2, 1959 FIG-Z FIG-3 INVENTORS V W, WW1, f F ia/w,

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United States Patent 3,011,091 RESONATOR FOR SINGLE-CIRCUIT MAGNETRON Alfred Christen, Baden, and Dieter Weber, Killwangen, Switzerland, assignors to Patelhold Patentverwertungs- & Eleklro-Holding A.-G., Glarus, Switzerland Filed Nov. 2, 1959, Ser. No. 850,185 Claims priority, application Switzerland Nov. 3, 1958 3 Claims. (Cl. SIS-39.73)

The present invention relates to magnetron oscillators of the single-circuit type and more particularly to an improved construction for the resonator component thereof.

A resonator component for a single-circuit magnetron is known to consist of a metallic toroid-shaped hollow body of, for example, rectangular section, whose circular-cylindrical face, directed toward the axis, is divided into a plurality of anodes which are alternately connected with the two circular side walls of the resonator normal to the axis. The provision of such a resonator with two rings, each connecting the anodes of equal phase with one another, to increase the oscillating stability, is known. The arrangement of such rings at the free ends of the anodes has proved particularly advantageous.

Especially in resonators for relatively high frequencies (for example, 4 GHz. and more), whose anodes present relatively small sections, the arrangement of rings just mentioned, while favorable in high-frequency technique, leads to considerable technological difiiculties. Because .the areas at which the rings can be soldered to the anodes are small, there is danger of failure of the soldering, the more so as during the soldering operation no great forces may be exerted on the anode system, to avoid deformation.

A great disadvantage in the known structural design of such resonators is further that the soldered areas are precisely where the highest temperatures occur when the magnetron is in operation. This brings about a limitation of the power loss and hence also of the useful power of the magnetron, not only because of the danger that the solder will melt, but already to avoid the occurrence of vapor pressures of disturbing magnitude.

The invention relates to an improved structural design of the resonator component of a single-circuit magnetron, in which the aforesaid disadvantages are eliminated. It aifords, as a technical advance, a reduction of rejects in the manufacture of the resonator and thus a reduction of the cost of the magnetron, as well as an increase of the power loss and effective power at the resonator.

A resonator designed according to the invention is characterized in that each ring together with the group of anodes assigned to it is of one-piece construction, and is connected at the anode roots, such as by soldering, with the corresponding side wall of the hollow body.

Representative embodiments of resonators for singlecircuit magnetrons according to the invention are illustrated in the accompanying drawings.

FIG. 1 of these drawings is a view in composite, angularly inclined radial sections of a resonator component showing the integrated anode and connecting ring structure, of the two anode groups;

FIG. 2 is a view in perspective of the utilized anode and connecting ring structure shown in FIG. 1;

given dimensions of "Ice FIG. 3 is a view in central vertical section of a slightly modified unitary anode and connecting ring structure taken on line 3-3 of FIG. 4; and

FIG. 4 is a view in top plan of the anode-ring structure shown in FIG. 3.

With reference now to the drawings and to FIGS. 1 and 2 in particular, the magnetron includes a metallic body, part of which is indicated by numeral 1 and which contains a hollow space 2 that forms the resonator cavity. Within this cavity are located the anodes which are arranged in two groups, the anodes of one group being interdigitated with the anodes of the other group. In FIG. 1, only an anode 5 of one group and an anode 6 of the other group are shown. The anodes 5 and 6 which are made from conductive material have thickened root portions 7 which are connected, as by soldering, to the side walls which, in part, define the limits of the cavity.

Anodes 5 are joined to one side wall 1a of the cavity and anodes 6 are joined to the other side wall 1b. The hollow body 1 is provided with a circular-cylindrical axial bore as part of the resonator cavity and the opposite ends of this bore are enlarged conically. Due to the fact that the anodes present root portions thickened radially outward, the necessary spacing from the other side wall of the body results as each piece is soldered in place to. its respective side wall. The opposite ends of the anodes 5,

which are free in the sense that they are not attached to the side wall of the cavity, are all electrically and struc, turally united by means of a ring portion 3. In a similar manner, the opposite ffree ends of the anodes -6 are all electrically and structurally united by means of a ring portion 4. I

As is more clearly illustrated in FIG. 2, the ring portion 3 together with the anodes 5 are made from a single piece of material, such as, for example, copper, and the general configuration is that of a crown. Consequently, the need for a soldered joint at the junction of the ring with the free ends of the anodes is eliminated by this newconstruction.

FIGS. 3 and 4 show another form of construction for the crown-shaped anode-ring piece, which is well suitable for manufacture in small lots. The desired radial thickening of the anodes 5' at their roots 7 is here achieved by folding the end portions of the strips forming the anodes back and forth upon themselves once or several times. The contact areas resulting between the individual layers of each strip are advantageously soldered together, either when connecting the piece with the hollow body or before, in a special operation. The ring portion is indicatedat 3'.

To enlarge the contact faces between the anodes and the side walls of the hollow body, the anode roots may be made wider in circumferential direction than the anodes themselves. When exceeding the width 360 deg.:n (n being the number of anodes), it becomes necessary to deform the anodes radially temporarily during insert-ion of the two crown-shaped pieces. When copper is used as material for the pieces, this is readily possible, as such deformations can be eliminated again at the latest when soldering'the pieces .into the hollow bodies- I It is evident from the figures that both the hollow body and the crown-shaped piecescan be designed in a manner which meets the requirements of expedient mass production. The manufacture of resonators according to the invention is possible at muchless expense than for instance the construction of multicavity resonators.

fWe. claim: p

.1. Resonator for a single-circuit magnetron in the form of a' toroid-shaped hollow body whose face toward the axis is comprised of two groups of interdigitated anodes,

said root portions of said anodes are thickened in a radially outward direction. I

3. A resonator as defined in claim 2 wherein the thickened root portions of said anodes are established by bending strip material back and forth upon itself one or more times.

References Cited in the file of this patent UNITED STATES PATENTS 2,500,430 Pierce Mar. 14, 1950 2,669,522 Hull Sept. 2, 1952 2,648,799 Lardelli Aug. 11, 1953 2,890,372

Dench June 9, 1959 

